Southwest Wisconsin Groundwater and Geology (SWIGG) Study

A multi-county effort to better understand private drinking water

Task Force on Water Quality Public HearingMay 8, 2019

"This information is preliminary and is subject to revision. It is being provided to meet the need for timely best science. The information is provided on the condition that neither the

U.S. Geological Survey nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information."

Background

• Jan. 2018 Moratorium & Manure Spreading Restriction requests

• Dr. Mark Borchardt & Dr. Madeline Gotkowitz Presented

• Invited Iowa & Lafayette Counties

• Grant County approved Groundwater study

• Grant, Iowa & Lafayette Counties discussed groundwater study

SWIGG Study Purpose:To give counties and the state better information about how to ensure residents have safe water to drink

Goals:– assess how widespread any well contamination is– identify sources of any contamination– analyze risk factors associated with well contamination– develop geological maps

Researchers:– Dr. Ken Bradbury, Director and State Geologist, WI Geological & Natural

History Survey– Dr. Mark Borchardt, Research Microbiologist, USDA Agricultural

Research Service– Joel Stokdyk, Biologist, U.S. Geological Survey

• Land Conservation Committees & Departments were created in 1982 to provide local leadership in protecting Wisconsin's land & water resources

• Authorized to implement DATCP, DNR, & County Conservation Programs– Farmland Preservation– Conservation Reserve Enhancement Program– Soil & Water Resource Management Program– Nonpoint Source Pollution Control Program– Land & Water Resource Management Plan

Wisconsin Geological and Natural History Survey

We provide objective scientific information about the geology,

mineral resources, and water resources of Wisconsin

• Hydrogeology• Geologic mapping• GIS

• Well construction analysis• Project guidance

DIVISION OF EXTENSION

• Interagency research lab, USDA-ARS and USGS

• Study occurrence, transport, and health effects of human pathogens in the environment

• Special focus on water quality and waterborne infectious disease

• More than 200 research publications

Laboratory for Infectious Disease and the Environment

Water and Environmental Analysis Lab (WEAL)

• UW-Stevens Point Center for Watershed Science and Education

• Wisconsin DNR and DATCP certified

• Outreach services• Well water education• Lake/river monitoring• GIS (mapping/modeling)

• Analyses Offered• Bacteria • Nutrients• Nitrate• Metals• Water chemistry• Pesticides and metabolites; pharmaceuticals

Simplified bedrock geology of Wisconsin

Distribution of carbonate rock within 50 feet of surface

• Bedrock aquifers• Carbonate rock near surface• Groundwater moves through fractures and

karst conduits• Flow can be very rapid• Sinkholes and karst features occur

• A very vulnerable landscape

Hydrogeology of Southwest Wisconsin

Bedding plane fractures are common in dolomite

Iowa County

Karst Features…

Evidence of subsurface dissolution and collapse

Geology is Important

• Geology & soil depth affect groundwater vulnerability• One objective is to develop geological maps

• Depth to bedrock• Rountree formation

• Data will be included in the analysis of well contamination factors

• Maps are resources for uses beyond this study

Well Construction is Important

Wells with shallow casings (cased above water table) are more vulnerable to contaminants originating at the land surface than more deeply-cased wells.

A preliminary review of well constriction identified over 900 such wells in Grant County alone.

Based on historical water sampling, southwest Wisconsin has a higher incidence of bacterial presence in wells than many other parts of the state.

from UWSP water quality viewer: www.uwsp.edu/cnr-ap/watershed/Pages/WellWaterViewer.aspx

Prior to this study, well sampling was relatively sparse.

from UWSP water quality viewer: www.uwsp.edu/cnr-ap/watershed/Pages/WellWaterViewer.aspx

What We’ve Done So Far:

Completed first round of randomized sampling (November, 2018). Homeowners collected samples Samples analyzed for total coliform, E. coli, & nitrate

by WEAL (UW-Stevens Point) Results reported to individual home owners in

December.

Completed second round of randomized sampling (April, 2019). Analyze for total coliform, E. coli, nitrate Laboratory analysis & data review in progress

Completed first round of sampling to determine fecal source of contamination (April, 2019).

How Widespread Is Contamination? Results from the first sampling event

Grant, 122, 40%

Iowa, 117, 39%

Lafayette, 62, 21%

Number of Wells Sampled = 301

• Proportioned approximately by population

• Samples from individual counties represent the 3-county region• Similar geology• Representative sample

Results of First Sampling Round, Nov. 9-10, 2018

*High nitrate is NO3--N > 10 mg/L

Percentages of wells with contaminants detected in the three counties generally exceed statewide averages.

“…special legislative committee commenced…in reaction to a preliminary report showing widespread contamination in private wells in southwestern Wisconsin.” -Task Force press release 2/11/19

Wells sampled

Total coliform E. coli

High nitrate*

Total coliform orhigh nitrate

SWIGG 301 34% 4% 16% 42%

Statewide 1997 534 23% 3% 7% -

Statewide 2013 3838 18% - 10% -

Statewide averages: Information on the quality of water found at community water systems and private wells. United States GAO/RCED-97-123, June 1997.Knobeloch L., Gorski P., Christenson M., and Anderson H. 2013. Private drinking water quality in rural Wisconsin. Journal of Environmental Health 75:16-20.

USGS disclaimer for study data: "Preliminary Information-Subject to Revision. Not for Citation or Distribution."

Percentage of wells positive for indicator bacteria or with high nitrate

Nitrate & Indicator Bacteria: Standard Water Quality Tests

Nitrate• Source: manure, human wastewater, & fertilizer• Maximum contaminant level: 10 ppm NO3

- -N

Total coliform• Source: fecal & non-fecal• Maximum contaminant level goal: 0

E. coli• Source: fecal• Maximum contaminant level goal: 0

All three: Indicate contamination but not the fecal source

42% of wells in the first sampling round had bacteria or high nitrate

Potential fecal sources• Septic systems: 16,092• Septage-applied s: ? • Hogs & pigs: 71,983 • Cattle & calves: 373,411

Other factors• Well characteristics• Rainfall• Geology

Data for potential fecal sources from county records & 2012 USDA Census of Agriculture

Where’s it coming from? What factors are involved?

USGS disclaimer for study data: "Preliminary Information-Subject to Revision. Not for Citation or Distribution."

What are potential sources of contamination?

Approach: Test a portion of contaminated wells for host-specific microorganisms• Random selection from contaminated wells• Laboratory staff collect samples• Test microbes unique to humans, cows, pigs

Outcome: Identify contamination source for a subset of wells

Fecal source is important, but other factors help us understand & address contamination

Which factors affect contamination?

Approach: Evaluate relationship between contamination & well characteristics

• Well & casing depth• Age• Depth to bedrock• Others

Outcome: Statistical assessment of factors that are related to contamination

SWIGG Study Outcomes

1. Percentage of wells contaminated using standard nitrate & bacteria tests

2. Determination of the contamination source (human, bovine, swine) for a subset of wells

3. Evaluation of well characteristics associated with contamination

4. Geologic maps for bedrock depth & Rountree formation

SWIGG Study: Local Funding

• Estimated total project cost: $203,000• Grant: Some 2018 dollars available• Iowa: Work it into plan for 2019 & 2020 budgets• Lafayette: Work it into the normal budget process

– Lafayette Co. for 2019: $15,470– Lafayette Ag Stewardship Alliance: $7,000– Private donations: $7,910

County Portion of SWIGG regionGrant 56%Iowa 26%Lafayette 18%

Funding Needs

Complete funding of SWIGG studyWith cost-sharing requirements County funds

aren’t anywhere near the amount needed to address water quality issues• 2019 average allocation per County is about $200,000

for staff and cost-sharing• Estimated need: Roughly $2-4 million per County per

year(based on an Iowa County impaired watershed estimate)

See WI Land & Water Association recommendations and estimates

Problem-solving Approach

Area-specific data and solutions• More capacity for microbial source tracking

Complex problems require complex solutions• Stakeholder collaboration, problem-solving, buy-in,

and accountability• Avoid thinking there is a quick fix or silver bullet• May need to look at agriculture policy and economics• May need to explore research and demonstrations of

new technology or practices

Solutions that are both feasible to implement and effective

Possible Solutions

IF contamination is correlated to well design:• Well code updates and region-specific standards• Well testing and inspection programs

IF contamination is correlated to septic systems:• Upgrade old septic systems• Analyze if current septic system standards can handle

modern needs

Incorporate groundwater considerations into land use planning and zoning

Possible Solutions

IF contamination is correlated to livestock:• Alternate manure handling methods and technology• Balance surface, groundwater, and odor concerns of

manure management

Nitrogen:• Develop nitrogen recommendations for groundwater

protection• Demonstrations of soil health and profitability with

different nitrogen strategies

Incentivize and facilitate adoption of conservation-based farming systems

Next Steps

• Continue outreach & education• Communicate with stakeholders• Complete the study

– Base any further action on the data

– Collaborate with stakeholders

– Seek region-specific, feasible, & effective solutions

Southwest Wisconsin Groundwater and Geology Study Team

Lynda Schweikert, Grant County Conservation, Sanitation and Zoning DeptKatie Abbott, Iowa County Land Conservation DepartmentTerry Loeffelholz, Lafayette County Land Conservation, Planning & Zoning DeptKen Bradbury, Director & State Geologist, WI Geological & Natural History SurveyJoel Stokdyk, Biologist, U.S. Geological SurveyMark Borchardt, Research Microbiologist, USDA Agricultural Research ServiceScott Laeser, Clean WisconsinBarry Hottmann, Community Educator, UW Extension-Iowa County Lafayette Ag Stewardship AllianceIowa County Uplands Watershed GroupWater & Environmental Analysis Laboratory, UW-Stevens Point